ISITC Europe has created a glossary in an attempt to provide the reader with a sufficient set of definitions to assist with understanding of the terminology surrounding this subject.

Term

Definition

Artificial Intelligence (AI)

Is the application(s) based on machine learning algorithms, used to analyse data repositories/data lakes to support decision making, evaluating data quality and identifying trader fraud.

Application Programming Interface (API)

API comprises a library of functions to support connectivity between applications data feeds and financial institutions.

BCBS 239

Basel Committee on Banking Supervision’s regulation number 239, titled, “Principles for effective risk data aggregation and risk reporting”, its aim is to reduce systemic risk by focusing on governance of financial data within an organisation.

Big Data

Refers to extremely large data sets captured within a repository. For financial institutions this takes the form of events associated with the life cycle of the trade and may include market data (i.e. pricing and analytics) and reference data (party, instrument and product). Typically closely related to AI (Artificial Intelligence). Also created to the concept of implementing a Data Lake where silos of transaction data are brought together.

Bi-temporal

The ability to link data items or group of data items that have independent timelines with others. For example, a trade event references parties, instrument or other identifiers, which themselves change over time. To support these data lineages it is important that validity from/to timestamps are captured to retain trade lifecycle integrity.

Block

A snapshot of a ledger at a specific point in time. A block should be sufficiently granular to support bi-temporal requirements of the business process it supports. It is important to appreciate that unlike a relational database persisted transaction the data is never amended it is always added to as a block. So therefore the data is immutable (see WORM). For example, a legal entity has a name, ISO LEI Identifier and a registered address, each have independent lifecycles of their own. It is therefore appropriate for each to be captured within separate blocks.

Blockchain

A collection of Blocks that are normally organized into a linear sequence. Over time, new Blocks are created and appended to the end of the chain.

Choreography

Refer to the logical chronological sequence of events/messages communicated between organisations and/or applications to support a business process. In simple terms this defines the message flows.

Concept

A concept is a unit of thought, idea or meaning. A Concept in the semantic domain is normally associated with a unique identifier; this is called an IRI (or URI).

Cryptocurrency (or crypto-currency)

Is a digital or virtual currency. As of January 2018, there were over thirteen hundred cryptocurrencies, the top traded ones are:

Are methods and techniques to facilitate secure communication of information. Blockchain and digital ledger use conventional public key cryptography to digitally sign each transaction. Along with choreography, this is one of the key building blocks required by any FinTech solution.

Hashing

Is a method of converting text, files or other objects into a fixed length key equivalent. A hash function is used to create this key and once a converted it allows the user to validate that the original has not been tampered with as well as facilitating faster database lookups. It is not a method for encrypting the data. Nonetheless, some hash algorithms are one-way meaning that they cannot be decrypted once generated. Bitcoin uses a SHA-2 (Secure Hash Algorithm 2)-256 in several parts of its infrastructure.

Data Architecture

Or Model Driven Architecture (MDA) is an approach composed of models, policies, rules and standards used to support the governance and dissemination of information in a consistent and unambiguous manner. This would normally comprise semantic, business, logical and physical models (database and/or message).

Data Authority

An upstream definitive source of specific information. This can take the form of a vendor feed, a gold copy or a front office trading platform.

Data Lake

See Big Data.

Data Lineage

Is the art of modelling the relationships between information through the life of a business process. This includes capturing its provenance, pedigree and what happens to it over the lifecycle of events.

Data Quality (or DQ)

The quality of data is normally assessed by qualitative and quantitative rules. The better the quality of information, the less the need to manually intervene in the workflow. High quality data enables Straight-Through-Processing (STP), the nirvana of the financial industry for decades and often requires the enrichment or validation of data via external reference data lookups.

Data Scientist

a person that analyses data and relationships of information to effectively support decision-making within an organisation. This individual should be able to understand the semantic meaning of the data to avoid erroneous quantitative outcomes especially as there is an expectation that one is assessing terabytes of data captured within a big data repository.

Distributed Ledger

Is a methodology where databases are spread across multiple countries, institutions or locations. Transactions are stored one after the other in a continuous ledger.

DLT

Distributed Ledger Technologies make up a framework that allows for the synchronization of information, in a consistent form across multiple applications, sites and institutions reducing the need to transform and reinterpret. Removing the risk of misunderstandings and breaks in the trading lifecycle resulting in the need for manual intervention.

D-SIB

Domestic Systemically Important Banks are financial institutions that do not fit within the G-SIB criteria, however they are of sufficient domestic systemic importance making them subject to the stringent annual stress testing.

Dublin Core

Is an RDF vocabulary that supports key metadata terms, this includes the ability to identify the creator, support versioning, among others. This vocabulary is used to annotate ontologies constructed using OWL or SKOS. Dublin Core is also an ISO standard, ISO 15836.

FIBO

The Financial Industry Business Ontology (or FIBO), initiated by and developed through the EDM Council, comprises a number of financial ontologies that provide meaning to legal/business entities and financial products. For further information please refer to: https://spec.edmcouncil.org/fibo

FinTech

Is a catchall name given for 21st century technological innovation in the financial sector. It includes technologies, methodologies, Blockchain and DLT.

FSB

Financial Stability Board (FSB) is an international body, comprising of global governmental, central banks and regulator representatives, that monitors and makes recommendations about the global financial system. It successfully facilitated the creation of the processes and organisational structure to support the LEI, along with the creation of BCBS 239 regulation.

Graph

is a representation of how process, data and other things are connected, comprising nodes (or vertices) and relationships (or edges). It is useful for understanding processes and their use of data elements by providing a semantic representation of the business.

G-SIB

A Global Systemically Important Bank (G-SIB) is a bank that is normally referred to as a tier 1 financial institution. This categorisation is based on a number of criteria: size, cross-jurisdiction activity, complexity, and substitutability. The G-SIB must maintain a higher capital level – capital surcharge – compared to other banks. . The list of G-SIBs is published annually by the Financial Stability Board (FSB).

Initial Coin Offering (ICO)

Is a way that a virtual currency can acquire its initial funding. Unlike an IPO, an ICO is unregulated, therefore the risk of losing your investment is high.

Immutable record of transactions

It is one of the fundamental principles of Blockchain, namely that once published the transaction/document cannot be changed. Also see WORM.

IRI

Internationalized Resource Identifier is a unique string of characters to identify a Concept. When in a Unicode encoding this is normally referred to as URI. However URI infers an ASCII encoding.

JSON

Is a flat tag/value pair data format used by web service applications for representing simple constructs. If there is a need to capture complex hierarchical relationships then an XML data format would be more appropriate.

JSON-LD

JavaScript Object Notation for Linked Data, is a method of encoding Linked Data. For further information, please refer to: https://en.wikipedia.org/wiki/JSON-LD

Ledger

A collection of transactions normally recording economic transactions, that are appended to over time, based on WORM principles.

Knowledge Graph

See Graph.

Microservices

Essentially, microservice architecture is a method of developing software applications as a suite of independently deployable, small, modular services in which each service runs a unique process and communicates through a well-defined, lightweight mechanism to serve a business goal.

Microservices app containers

Are a collection of software components to support a specific task, ensuring that the minimal resources are deployed to complete a function. This in contrast to normal Operating System environments where the assumption is that all components are available for applications to use at the time of execution. Multiple containers can be triggered independently on a single Operating System instance.

Mining (or cryptomining)

Is the process in which transactions using cryptocurrency are verified and added to a public blockchain digital ledger.

Ontology

A formal model of concepts, the relationships that connect them, and constraints on the ways that concepts and relationships can be combined. These are complex relationships and may not result in a simple hierarchical structure.

Operating model (Centralised)

The main advantage of a centralised model is that there is a definitive authoritative “gold copy” source of information and in general one can expect quicker response times in identifying the definitive state given there are no dependencies on other participating nodes. Nonetheless, this must be balanced against the possibility of a single point of failure.

Operating Model (Federated)

This would normally take the form of specific Data Authorities being responsible for publishing certain types of information. This can take the form of a multicast network, where subscriber nodes put out broadcast requests, which can be responded to by one or more data authorities. Typically, this involves a great deal of protocol complexity (or Choreography), given the need to manage what is the authoritative copy of information at any point in time. This also can result into introducing latency as the primary node for souring information may respond slower than a secondary publisher. In such scenarios one needs to capture the Data Quality (DQ) rating and staleness indicators, so that subscribers do not make decisions based on potentially inaccurate or stale information.

Operating Model (Distributed)

Is a model that takes aspects from the Federated model, however the data authorities may be numerous and there may not be a definitive authoritative source to validate against. Given the greater number of data authorities, ownership, traceability, pedigree and provenance becomes key, even more so than a Federated model.

OWL

The W3C Web Ontology Language is a Semantic Web language designed to represent rich and complex knowledge about things, groups of things, and relations between things. It allows one to represent hierarchical class relationships and capture properties, constraints among other things. For further information, please refer to: https://www.w3.org/OWL/. There are various syntax conventions by which OWL can be represented (see “TTL” below).

Pedigree

Capturing the meta data to provide the appropriate confidence in the ancestry of the information.

PERDARR

Principles for Effective Risk Data Aggregation and Risk Reporting, the title of BCBS regulation 239.

Permissioned Ledger

Only preselected participants have the rights to enrich/append or create a Ledger.

Provenance

Is the history of the ownership in the dissemination of information.

PROV-O

Prov-O is a W3C initiate to capture It provides a set of classes, properties, and restrictions that can be used to represent and interchange provenance.

RegTech

Is the deployment of new technological innovations to improve efficiency and simplify process to adhere to regulatory compliance, with the aim of reducing the risk of financial penalties due to poor governance.
A particular area requiring improvement is the onbaording process. In addition, it will provide organisations with the capability to support data quality assessments and identify where improvements are required.

RESTful Services

REpresentational State Transfer is an network interface service that takes advantage of existing protocols, normally HTTP. A RESTful service can be easily developed using existing technologies such as Python, .NET, or Java, and handle JSON and XML data formats.

RDF/XML

Resource Description Framework, normally encoded in XML, provides the framework to define the relationship between concepts; this is usually referred to as a “Triple”. For further information, please refer to: https://www.w3.org/TR/REC-rdf-syntax/

SIFI

A Systemically Important Financial Institution is a bank, insurance company or other financial institution whose failure could trigger a economic financial crisis. Such institutions are broken down in to two main categories (G-SIB and D-SIB). Basically, these are organisations referred to as “Too big to fail”.

SKOS

Simple Knowledge Organization System is a W3C recommendation designed for representing classification schemes and taxonomies. Like OWL, SKOS is an RDF-based vocabulary. Unlike the class hierarchy one might develop in OWL, SKOS provides the ability to create hierarchies that utilize different types of relationships, e.g., is-a-part/member-of and as such, it provides the opportunity to support classifications and taxonomies across a broad range of information and use cases. For further information, please refer to: https://www.w3.org/SKOS/

Smart Contracts

Is the representation of legal contracts or elements of legal contracts (i.e. trade events) in the form of executable code and data objects that can automatically be triggered as part of a business process, thereby enabling more efficient straight through processing in a DLT architecture. To facilitate this there is a realisation that Industry wide standards are required and ISDA is at the forefront of promoting this given their experience in defining Master Agreements. For further information go to: http://www2.isda.org/attachment/ODcwMA==/Infrastructure%20white%20paper.pdf

Taxonomy

Is a hierarchy of concepts, the relations are normally parent/child, superclass/subClass, or broader/narrower.

Triple

The semantic web at the atomic level can be broken down into Triples. An OWL or SKOS based model can also be expressed in Triples. A Triple provides the capability to support data linkages between concepts and comprises three of parts:

Subject

The thing upon which the relationship/modification is to be applied to.

Predicate

Describes the relationship between the Subject and Object.

Object

The thing the Predicate is acting upon, also known as the target.

The object of one Triple can be the subject of another triple, allowing one to represent relationships between items, this lends itself being visualising data in a graphical form and also providing linkages between model objects.

Subject

Predicate

Object

Equities

Can take the form of

Common/ordinary shares (S)

Debt Instrument

pays a

Coupon

Subjects and Objects are Concepts and in Ontologies are uniquely identified using IRIs.

TTL

Terse RDF Triple Language or Turtle/TTL is a syntax convention that represents the Web Ontology Language (OWL). For further information on this OWL syntax and details regarding how it is structured please refer to https://www.w3.org/TeamSubmission/turtle/.

Unpermissioned Ledger

Refers to a ledger that anyone can contribute to and provides permanent record that cannot be edited. Possible use cases include a last will and testament or a land registry.

URI

Uniform Resource Identifier is a unique string of characters to identify a concept and infers an ASCII encoding. Also see IRI.

WORM

Write Once Read Many, refers to a method of recording data in a database, where information is never changed or deleted once stored. New information is appended to the database.

If the reader wishes to contribute to or challenge the content of the Glossary, please complete the following details:

Is the application(s) based on machine learning algorithms, used to analyse data repositories/data lakes to support decision making, evaluating data quality and identifying trader fraud.

Application Programming Interface (API)

API comprises a library of functions to support connectivity between applications data feeds and financial institutions.

BCBS 239

Basel Committee on Banking Supervision’s regulation number 239, titled, “Principles for effective risk data aggregation and risk reporting”, its aim is to reduce systemic risk by focusing on governance of financial data within an organisation.

Big Data

Refers to extremely large data sets captured within a repository. For financial institutions this takes the form of events associated with the life cycle of the trade and may include market data (i.e. pricing and analytics) and reference data (party, instrument and product). Typically closely related to AI (Artificial Intelligence). Also created to the concept of implementing a Data Lake where silos of transaction data are brought together.

Bi-temporal

The ability to link data items or group of data items that have independent timelines with others. For example, a trade event references parties, instrument or other identifiers, which themselves change over time. To support these data lineages it is important that validity from/to timestamps are captured to retain trade lifecycle integrity.

Block

A snapshot of a ledger at a specific point in time. A block should be sufficiently granular to support bi-temporal requirements of the business process it supports. It is important to appreciate that unlike a relational database persisted transaction the data is never amended it is always added to as a block. So therefore the data is immutable (see WORM). For example, a legal entity has a name, ISO LEI Identifier and a registered address, each have independent lifecycles of their own. It is therefore appropriate for each to be captured within separate blocks.

Blockchain

A collection of Blocks that are normally organized into a linear sequence. Over time, new Blocks are created and appended to the end of the chain.

Choreography

Refer to the logical chronological sequence of events/messages communicated between organisations and/or applications to support a business process. In simple terms this defines the message flows.

Concept

A concept is a unit of thought, idea or meaning. A Concept in the semantic domain is normally associated with a unique identifier; this is called an IRI (or URI).

Cryptocurrency (or crypto-currency)

Is a digital or virtual currency. As of January 2018, there were over thirteen hundred cryptocurrencies, the top traded ones are:

Are methods and techniques to facilitate secure communication of information. Blockchain and digital ledger use conventional public key cryptography to digitally sign each transaction. Along with choreography, this is one of the key building blocks required by any FinTech solution.

Hashing

Is a method of converting text, files or other objects into a fixed length key equivalent. A hash function is used to create this key and once a converted it allows the user to validate that the original has not been tampered with as well as facilitating faster database lookups. It is not a method for encrypting the data. Nonetheless, some hash algorithms are one-way meaning that they cannot be decrypted once generated. Bitcoin uses a SHA-2 (Secure Hash Algorithm 2)-256 in several parts of its infrastructure.

Data Architecture

Or Model Driven Architecture (MDA) is an approach composed of models, policies, rules and standards used to support the governance and dissemination of information in a consistent and unambiguous manner. This would normally comprise semantic, business, logical and physical models (database and/or message).

Data Authority

An upstream definitive source of specific information. This can take the form of a vendor feed, a gold copy or a front office trading platform.

Data Lake

See Big Data.

Data Lineage

Is the art of modelling the relationships between information through the life of a business process. This includes capturing its provenance, pedigree and what happens to it over the lifecycle of events.

Data Quality (or DQ)

The quality of data is normally assessed by qualitative and quantitative rules. The better the quality of information, the less the need to manually intervene in the workflow. High quality data enables Straight-Through-Processing (STP), the nirvana of the financial industry for decades and often requires the enrichment or validation of data via external reference data lookups.

Data Scientist

a person that analyses data and relationships of information to effectively support decision-making within an organisation. This individual should be able to understand the semantic meaning of the data to avoid erroneous quantitative outcomes especially as there is an expectation that one is assessing terabytes of data captured within a big data repository.

Distributed Ledger

Is a methodology where databases are spread across multiple countries, institutions or locations. Transactions are stored one after the other in a continuous ledger.

DLT

Distributed Ledger Technologies make up a framework that allows for the synchronization of information, in a consistent form across multiple applications, sites and institutions reducing the need to transform and reinterpret. Removing the risk of misunderstandings and breaks in the trading lifecycle resulting in the need for manual intervention.

D-SIB

Domestic Systemically Important Banks are financial institutions that do not fit within the G-SIB criteria, however they are of sufficient domestic systemic importance making them subject to the stringent annual stress testing.

Dublin Core

Is an RDF vocabulary that supports key metadata terms, this includes the ability to identify the creator, support versioning, among others. This vocabulary is used to annotate ontologies constructed using OWL or SKOS. Dublin Core is also an ISO standard, ISO 15836.

FIBO

The Financial Industry Business Ontology (or FIBO), initiated by and developed through the EDM Council, comprises a number of financial ontologies that provide meaning to legal/business entities and financial products. For further information please refer to: https://spec.edmcouncil.org/fibo

FinTech

Is a catchall name given for 21st century technological innovation in the financial sector. It includes technologies, methodologies, Blockchain and DLT.

FSB

Financial Stability Board (FSB) is an international body, comprising of global governmental, central banks and regulator representatives, that monitors and makes recommendations about the global financial system. It successfully facilitated the creation of the processes and organisational structure to support the LEI, along with the creation of BCBS 239 regulation.

Graph

is a representation of how process, data and other things are connected, comprising nodes (or vertices) and relationships (or edges). It is useful for understanding processes and their use of data elements by providing a semantic representation of the business.

G-SIB

A Global Systemically Important Bank (G-SIB) is a bank that is normally referred to as a tier 1 financial institution. This categorisation is based on a number of criteria: size, cross-jurisdiction activity, complexity, and substitutability. The G-SIB must maintain a higher capital level – capital surcharge – compared to other banks. . The list of G-SIBs is published annually by the Financial Stability Board (FSB).

Initial Coin Offering (ICO)

Is a way that a virtual currency can acquire its initial funding. Unlike an IPO, an ICO is unregulated, therefore the risk of losing your investment is high.

Immutable record of transactions

It is one of the fundamental principles of Blockchain, namely that once published the transaction/document cannot be changed. Also see WORM.

IRI

Internationalized Resource Identifier is a unique string of characters to identify a Concept. When in a Unicode encoding this is normally referred to as URI. However URI infers an ASCII encoding.

JSON

Is a flat tag/value pair data format used by web service applications for representing simple constructs. If there is a need to capture complex hierarchical relationships then an XML data format would be more appropriate.

JSON-LD

JavaScript Object Notation for Linked Data, is a method of encoding Linked Data. For further information, please refer to: https://en.wikipedia.org/wiki/JSON-LD

Ledger

A collection of transactions normally recording economic transactions, that are appended to over time, based on WORM principles.

Knowledge Graph

See Graph.

Microservices

Essentially, microservice architecture is a method of developing software applications as a suite of independently deployable, small, modular services in which each service runs a unique process and communicates through a well-defined, lightweight mechanism to serve a business goal.

Microservices app containers

Are a collection of software components to support a specific task, ensuring that the minimal resources are deployed to complete a function. This in contrast to normal Operating System environments where the assumption is that all components are available for applications to use at the time of execution. Multiple containers can be triggered independently on a single Operating System instance.

Mining (or cryptomining)

Is the process in which transactions using cryptocurrency are verified and added to a public blockchain digital ledger.

Ontology

A formal model of concepts, the relationships that connect them, and constraints on the ways that concepts and relationships can be combined. These are complex relationships and may not result in a simple hierarchical structure.

Operating model (Centralised)

The main advantage of a centralised model is that there is a definitive authoritative “gold copy” source of information and in general one can expect quicker response times in identifying the definitive state given there are no dependencies on other participating nodes. Nonetheless, this must be balanced against the possibility of a single point of failure.

Operating Model (Federated)

This would normally take the form of specific Data Authorities being responsible for publishing certain types of information. This can take the form of a multicast network, where subscriber nodes put out broadcast requests, which can be responded to by one or more data authorities. Typically, this involves a great deal of protocol complexity (or Choreography), given the need to manage what is the authoritative copy of information at any point in time. This also can result into introducing latency as the primary node for souring information may respond slower than a secondary publisher. In such scenarios one needs to capture the Data Quality (DQ) rating and staleness indicators, so that subscribers do not make decisions based on potentially inaccurate or stale information.

Operating Model (Distributed)

Is a model that takes aspects from the Federated model, however the data authorities may be numerous and there may not be a definitive authoritative source to validate against. Given the greater number of data authorities, ownership, traceability, pedigree and provenance becomes key, even more so than a Federated model.

OWL

The W3C Web Ontology Language is a Semantic Web language designed to represent rich and complex knowledge about things, groups of things, and relations between things. It allows one to represent hierarchical class relationships and capture properties, constraints among other things. For further information, please refer to: https://www.w3.org/OWL/. There are various syntax conventions by which OWL can be represented (see “TTL” below).

Pedigree

Capturing the meta data to provide the appropriate confidence in the ancestry of the information.

PERDARR

Principles for Effective Risk Data Aggregation and Risk Reporting, the title of BCBS regulation 239.

Permissioned Ledger

Only preselected participants have the rights to enrich/append or create a Ledger.

Provenance

Is the history of the ownership in the dissemination of information.

PROV-O

Prov-O is a W3C initiate to capture It provides a set of classes, properties, and restrictions that can be used to represent and interchange provenance.

RegTech

Is the deployment of new technological innovations to improve efficiency and simplify process to adhere to regulatory compliance, with the aim of reducing the risk of financial penalties due to poor governance.
A particular area requiring improvement is the onbaording process. In addition, it will provide organisations with the capability to support data quality assessments and identify where improvements are required.

RESTful Services

REpresentational State Transfer is an network interface service that takes advantage of existing protocols, normally HTTP. A RESTful service can be easily developed using existing technologies such as Python, .NET, or Java, and handle JSON and XML data formats.

RDF/XML

Resource Description Framework, normally encoded in XML, provides the framework to define the relationship between concepts; this is usually referred to as a “Triple”. For further information, please refer to: https://www.w3.org/TR/REC-rdf-syntax/

SIFI

A Systemically Important Financial Institution is a bank, insurance company or other financial institution whose failure could trigger a economic financial crisis. Such institutions are broken down in to two main categories (G-SIB and D-SIB). Basically, these are organisations referred to as “Too big to fail”.

SKOS

Simple Knowledge Organization System is a W3C recommendation designed for representing classification schemes and taxonomies. Like OWL, SKOS is an RDF-based vocabulary. Unlike the class hierarchy one might develop in OWL, SKOS provides the ability to create hierarchies that utilize different types of relationships, e.g., is-a-part/member-of and as such, it provides the opportunity to support classifications and taxonomies across a broad range of information and use cases. For further information, please refer to: https://www.w3.org/SKOS/

Smart Contracts

Is the representation of legal contracts or elements of legal contracts (i.e. trade events) in the form of executable code and data objects that can automatically be triggered as part of a business process, thereby enabling more efficient straight through processing in a DLT architecture. To facilitate this there is a realisation that Industry wide standards are required and ISDA is at the forefront of promoting this given their experience in defining Master Agreements. For further information go to: http://www2.isda.org/attachment/ODcwMA==/Infrastructure%20white%20paper.pdf

Taxonomy

Is a hierarchy of concepts, the relations are normally parent/child, superclass/subClass, or broader/narrower.

Triple

The semantic web at the atomic level can be broken down into Triples. An OWL or SKOS based model can also be expressed in Triples. A Triple provides the capability to support data linkages between concepts and comprises three of parts:

Subject

The thing upon which the relationship/modification is to be applied to.

Predicate

Describes the relationship between the Subject and Object.

Object

The thing the Predicate is acting upon, also known as the target.

The object of one Triple can be the subject of another triple, allowing one to represent relationships between items, this lends itself being visualising data in a graphical form and also providing linkages between model objects.

Subject

Predicate

Object

Equities

Can take the form of

Common/ordinary shares (S)

Debt Instrument

pays a

Coupon

Subjects and Objects are Concepts and in Ontologies are uniquely identified using IRIs.

TTL

Terse RDF Triple Language or Turtle/TTL is a syntax convention that represents the Web Ontology Language (OWL). For further information on this OWL syntax and details regarding how it is structured please refer to https://www.w3.org/TeamSubmission/turtle/.

Unpermissioned Ledger

Refers to a ledger that anyone can contribute to and provides permanent record that cannot be edited. Possible use cases include a last will and testament or a land registry.

URI

Uniform Resource Identifier is a unique string of characters to identify a concept and infers an ASCII encoding. Also see IRI.

WORM

Write Once Read Many, refers to a method of recording data in a database, where information is never changed or deleted once stored. New information is appended to the database.